BMW Cooling System Parts & Accessories for BMW X5 M S63 4.4L

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The cooling system is arguably the weakest point in numerous BMWs. If you drive an aging BMW or plan on taking your car to the track like we do, we recommend beefing up your cooling system before going to the track. Generally, the main components in your cooling system that are prone to failure include the following: expansion tank, factory hoses, water pump, thermostat, fan (especially if your vehicle comes factory with a clutch fan), and radiator. Factory BMW expansion tanks are plastic and prone to either breaking off at connection points or combusting. As factory rubber hoses age they either crack or break over time - we offer silicone cooling hose upgrades for most applications to avoid future failures. If you have an older vehicle, your water pump likely comes from the factory with a plastic impeller - we offer upgraded water pumps with metal impellers that are far more reliable. Newer model BMWs utilize electric water pumps - BMW spent millions of dollars engineering these water pumps, but they fail so often that we recommend replacing at 60,000 mile service intervals to avoid being stranded on the side of the road. In terms of thermostats, we offer various upgraded thermostats for racing applications. If your BMW utilizes a clutch fan from the factory, we have several options available in terms of universal electric fans - we recommend replacing these to avoid sending brittle plastic fan blades through your hood. For radiators, we recommend swapping out your radiator for one that does not use plastic connection points like your factory radiator.

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Thermostat Replacement kit - 90C
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Packaged by Turner - Corporate Logo
T#:15744051
Part#: 82142209769KT
In Stock
Sale - Save 3% $ 146.99

This product was last offered at the strikethrough price on
05-03-2026

$ 142.74 USD
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Sale - Save 3%
$ 146.99

This product was last offered at the strikethrough price on
05-03-2026

$ 142.74 USD
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Packaged by Turner - Corporate Logo
T#:554065
Part#: 11517548263KT3
In Stock
Sale - Save 31% $ 336.99

This product was last offered at the strikethrough price on
05-03-2026

$ 232.61 USD
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Sale - Save 31%
$ 336.99

This product was last offered at the strikethrough price on
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$ 232.61 USD
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The water pumps in BMW's should be serviced near 80,000 miles and may become an issue often times leaving the owner stranded. The aftermarket kit offered provides a single stop for water pump and thermostat replacement needs to save the search and get you back on the road.

Kit includes:

  • Thermostat
  • Water pump
  • Coolant

 

This item fits the following BMW Engines: 
N63,N63N,S63,N62N 

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Performance Water Pump & Thermostat Kit - 90*C - S63
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Packaged by Turner - Corporate Logo
T#:30397428
Part#: 11537843738KT2
Ships on Oct 7, 2026
$ 579.99

This product was last offered at the strikethrough price on
04-28-2026

$ 549.99 USD
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$ 549.99 USD
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The water pump is a known weak point across all BMW models, requiring servicing every 60,000 miles. Along with the water pump, it’s wise to replace the thermostat to ensure your cooling system operates at peak efficiency.

This kit features a 90°C (194°F) thermostat from Hamburg Technic, which opens approximately 15°C earlier than the standard factory thermostat. This lower temperature is particularly advantageous for performance-focused applications.

What's Included:

Genuine BMW Mechanical Water Pump Assembly (11537843738) Hamburg Technic Performance Thermostat - 90°C/194°F (11537586885) Genuine BMW Coolant/Antifreeze - Diluted, 1 Gallon (82141467704) Benefits of a Lower Thermostat Temperature:

Enhanced Engine Cooling: Opens sooner to reduce engine temperature more effectively. Improved Performance: Keeps engine components cooler, allowing for better performance in high-stress conditions. Extended Engine Life: Reduces thermal stress on engine parts, promoting longevity. Prevents Overheating: Helps to avoid overheating in demanding driving scenarios. Optimized Fuel Efficiency: Maintains ideal engine temperature for efficient fuel combustion. Elevate your BMW's cooling system and performance with this expertly curated kit from Turner Motorsport.

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Bav Auto Spill-Proof Coolant / Antifreeze Funnel
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Bav Auto Tools - Corporate Logo
T#:580395
Part#: B8800082
In Stock
Sale - Save 15% $ 33.99

This product was last offered at the strikethrough price on
08-19-2026

$ 28.99 USD
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Sale - Save 15%
$ 33.99

This product was last offered at the strikethrough price on
08-19-2026

$ 28.99 USD
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Multiple adapters include to fit a variety of vehicles.

Vargas Turbo Technologies - Corporate Logo
T#:7530036
Part#: COOLANTCAPBLUE
In Stock
$ 79.99 USD
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$ 79.99 USD
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VTT is proud to offer their billet replacement for the factory plastic Coolant Reservoir cap. This cap does away with the weak plastic cap while adding some pop, and color to your engine bay. This coolant cap retains ALL of the factory provisions by simply allowing you to snap the factory pressure-relief into the new Billet Cap. VTT also designed these caps to complement their N5X Billet Oil caps, N5XBillet Oil filter housing caps, and Billet Power Steering cap, so all 4 will have the same design. These caps are offered in 4 colors – Red, Black, Blue, and Clear anodized Replaces Genuine BMW Reservoir Cap # 17117639020 Note: Fitment includes 99% of all BMW with a coolant Reservoir tank from the E series forward, meaning then fit even the brand New G8X M3/4 with the S58, all B58, etc. If your BMW is an E90 or newer this cap most likely will fit
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Vargas Turbo Technologies - Corporate Logo
T#:7530034
Part#: COOLANTCAPRED
In Stock
$ 79.99 USD
Free Shipping
$ 79.99 USD
Free Shipping
VTT is proud to offer their billet replacement for the factory plastic Coolant Reservoir cap. This cap does away with the weak plastic cap while adding some pop, and color to your engine bay. This coolant cap retains ALL of the factory provisions by simply allowing you to snap the factory pressure-relief into the new Billet Cap. VTT also designed these caps to complement their N5X Billet Oil caps, N5XBillet Oil filter housing caps, and Billet Power Steering cap, so all 4 will have the same design. These caps are offered in 4 colors – Red, Black, Blue, and Clear anodized Replaces Genuine BMW Reservoir Cap # 17117639020 Note: Fitment includes 99% of all BMW with a coolant Reservoir tank from the E series forward, meaning then fit even the brand New G8X M3/4 with the S58, all B58, etc. If your BMW is an E90 or newer this cap most likely will fit
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Race German - Corporate Logo
T#:6827887
Part#: RGCTSAM12
In Stock
$ 35.99 USD
Free Shipping on orders $49 and up
Race German has devoted themselves to providing quality products for late model BMWs that cover both street and track applications. Race German has now grown their catalog to a wide variety of models and products geared towards keeping your car looking and running nice. For those looking to install an aftermarket coolant temp gauge, Race German has the perfect accessory for you! This adapter is machined out of aluminum and splices into your upper radiator hose. Perfect for use with Race German's E30 temperature gauge but has compatibility with a wire variety of other cars as well! Features: Tapped for M12x1.5 sized sensor 38mm diameter outlets which fit most BMW hoses Includes 2x hose clamps **Does not include temp sensor
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Bav Auto Fan Clutch Wrench - 32mm
10X Entries Into Our F80 M3 Sweepstakes
Bav Auto Tools - Corporate Logo
T#:580348
Part#: B8800019
In Stock
Sale - Save 20% $ 29.99

This product was last offered at the strikethrough price on
05-03-2026

$ 23.99 USD
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Sale - Save 20%
$ 29.99

This product was last offered at the strikethrough price on
05-03-2026

$ 23.99 USD
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Used to remove your fan clutch

Bav Auto Tools - Corporate Logo
T#:580397
Part#: B8800084
In Stock
Sale - Save 15% $ 146.99

This product was last offered at the strikethrough price on
05-03-2026

$ 124.94 USD
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Sale - Save 15%
$ 146.99

This product was last offered at the strikethrough price on
05-03-2026

$ 124.94 USD
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Race German - Corporate Logo
T#:6827888
Part#: RGCTSA1/8NPT
In Stock
$ 35.99 USD
Free Shipping on orders $49 and up
Race German has devoted themselves to providing quality products for late model BMWs that cover both street and track applications. Race German has now grown their catalog to a wide variety of models and products geared towards keeping your car looking and running nice. For those looking to install an aftermarket coolant temp gauge, Race German has the perfect accessory for you! This adapter is machined out of aluminum and splices into your upper radiator hose. Perfect for use with Race German's E30 temperature gauge but has compatibility with a wire variety of other cars as well! Features: Tapped for 1/8NPT sized sensor 38mm diameter outlets which fit most BMW hoses Includes 2x hose clamps **Does not include temp sensor
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Genuine MINI - Corporate Logo
T#:28337931
Part#: 17135A1BD89
In Stock
26% off MSRP $ 34.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 25.99 USD
Free Shipping on orders $49 and up
26% off MSRP
$ 34.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 25.99 USD
Free Shipping on orders $49 and up
Bavarian Autosport - Corporate Logo
T#:638093
Part#: 17138621092
In Stock
Sale - Save 20% $ 60.99

This product was last offered at the strikethrough price on
05-03-2026

$ 48.79 USD
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Sale - Save 20%
$ 60.99

This product was last offered at the strikethrough price on
05-03-2026

$ 48.79 USD
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Replace your old expansion tank to prevent potential failure or leaks. Includes a brand new coolant level sensor.


VTT Billet Coolant Reservoir Cap - Anodized Clear - Most BMWs 2006+ (...
This coolant cap retains ALL of the factory provisions by simply allowing you to snap t...
2X Entries Into Our F80 M3 Sweepstakes
Vargas Turbo Technologies - Corporate Logo
T#:7530035
Part#: COOLANTCAPRAW
Back Ordered
$ 78.99 USD
Free Shipping
$ 78.99 USD
Free Shipping
VTT is proud to offer their billet replacement for the factory plastic Coolant Reservoir cap. This cap does away with the weak plastic cap while adding some pop, and color to your engine bay. This coolant cap retains ALL of the factory provisions by simply allowing you to snap the factory pressure-relief into the new Billet Cap. VTT also designed these caps to complement their N5X Billet Oil caps, N5XBillet Oil filter housing caps, and Billet Power Steering cap, so all 4 will have the same design. These caps are offered in 4 colors – Red, Black, Blue, and Clear anodized Replaces Genuine BMW Reservoir Cap # 17117639020 Note: Fitment includes 99% of all BMW with a coolant Reservoir tank from the E series forward, meaning then fit even the brand New G8X M3/4 with the S58, all B58, etc. If your BMW is an E90 or newer this cap most likely will fit
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Precision Raceworks - Corporate Logo
T#:38128032
Part#: 201-0394-SIL
Ships in 7 Business Days
$ 94.99 USD
Free Shipping on orders $49 and up

BMW Silver Auxiliary Coolant Reservoir Cap is the perfect upgrade for BMW owners looking to enhance both the aesthetics and functionality of their engine bay. Unlike generic aftermarket caps that overlook critical pressure regulation, this precision-engineered cap retains the OEM pressure release functionality, ensuring safe and reliable coolant system performance.

Crafted from high-quality billet aluminum, this reservoir cap offers superior durability and resistance to heat and fluids, preventing warping or degradation over time. Unlike adhesive-based cap covers that can loosen or fall off, this cap is a direct replacement for the factory component, providing a secure, high-performance solution.

  • OEM pressure release functionality – Maintains proper system regulation for optimal coolant performance
  • Premium billet aluminum construction – Offers enhanced durability and longevity
  • Direct replacement design – Secure fit without adhesives or modifications
  • Resistant to heat and fluids – Ensures long-lasting reliability in extreme conditions
  • Performance-inspired look – Adds a sleek, high-end appearance to your engine bay
  • Upgraded durability – Prevents cracking, leaks, and premature wear

Upgrade your BMW’s cooling system with the BMW Silver Auxiliary Coolant Reservoir Cap, blending performance, reliability, and premium styling.

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Bav Auto Angled Hose Pinch Plier Set - 2pc
10X Entries Into Our F80 M3 Sweepstakes
Bav Auto Tools - Corporate Logo
T#:580379
Part#: B8800058
In Stock
Sale - Save 25% $ 32.99

This product was last offered at the strikethrough price on
05-03-2026

$ 24.74 USD
Free Shipping on orders $49 and up
Sale - Save 25%
$ 32.99

This product was last offered at the strikethrough price on
05-03-2026

$ 24.74 USD
Free Shipping on orders $49 and up
Angled jaws close, creating a complete seal every time you use them - the jaws are offset, making it possible to use in hard-to-reach locations. Made of glass-filled nylon for extra strength. These are perfect for use with brake lines, etc.
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Rein Coolant Expansion Tank - E70
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:592030
Part#: 17138621092
In Stock at Vendor
$ 100.99 USD
Free Shipping
$ 100.99 USD
Free Shipping
Replace your cracked or faded tank

Vargas Turbo Technologies - Corporate Logo
T#:7530033
Part#: COOLANTCAPBLK
In Stock
$ 79.99 USD
Free Shipping
$ 79.99 USD
Free Shipping
VTT is proud to offer their billet replacement for the factory plastic Coolant Reservoir cap. This cap does away with the weak plastic cap while adding some pop, and color to your engine bay. This coolant cap retains ALL of the factory provisions by simply allowing you to snap the factory pressure-relief into the new Billet Cap. VTT also designed these caps to complement their N5X Billet Oil caps, N5XBillet Oil filter housing caps, and Billet Power Steering cap, so all 4 will have the same design. These caps are offered in 4 colors – Red, Black, Blue, and Clear anodized Replaces Genuine BMW Reservoir Cap # 17117639020 Note: Fitment includes 99% of all BMW with a coolant Reservoir tank from the E series forward, meaning then fit even the brand New G8X M3/4 with the S58, all B58, etc. If your BMW is an E90 or newer this cap most likely will fit
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Rein Water Pump - N63 S63
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:393385
Part#: 11517548263
In Stock
$ 215.99 USD
Free Shipping
$ 215.99 USD
Free Shipping
In German, Rein means Pure. In the automotive industry the Rein name has quickly come to represent quality. With fitments for some of the worldaEURtms finest automobiles including BMW and Mini and guaranteed OE quality, Rein is a name you can trust. Replace your water pump with Rein to get your cooling system back in check.
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Rein Expansion Tank Cap
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:384807
Part#: 17117639021
In Stock
$ 16.99 USD
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Cap for plastic expansion tank
Rein Coolant Expansion Tank - E70
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:592023
Part#: 17137647290
Ships in 3 Business Days
$ 85.99 USD
Free Shipping
$ 85.99 USD
Free Shipping
Plastic expansion tanks have a limited lifespan - replace every 80,000 miles

Precision Raceworks - Corporate Logo
T#:38128031
Part#: 201-0394-BLK
Ships in 9 Business Days
$ 94.99 USD
Free Shipping on orders $49 and up

BMW Black Auxiliary Coolant Reservoir Cap is the perfect upgrade for BMW owners looking to enhance both the aesthetics and functionality of their engine bay. Unlike generic aftermarket caps that overlook critical pressure regulation, this precision-engineered cap retains the OEM pressure release functionality, ensuring safe and reliable coolant system performance.

Crafted from high-quality billet aluminum, this reservoir cap offers superior durability and resistance to heat and fluids, preventing warping or degradation over time. Unlike adhesive-based cap covers that can loosen or fall off, this cap is a direct replacement for the factory component, providing a secure, high-performance solution.

  • OEM pressure release functionality – Maintains proper system regulation for optimal coolant performance
  • Premium billet aluminum construction – Offers enhanced durability and longevity
  • Direct replacement design – Secure fit without adhesives or modifications
  • Resistant to heat and fluids – Ensures long-lasting reliability in extreme conditions
  • Performance-inspired look – Adds a sleek, high-end appearance to your engine bay
  • Upgraded durability – Prevents cracking, leaks, and premature wear

Upgrade your BMW’s cooling system with the BMW Black Auxiliary Coolant Reservoir Cap, blending performance, reliability, and premium styling.

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Precision Raceworks - Corporate Logo
T#:38128029
Part#: 201-0394-BLU
Ships in 9 Business Days
$ 94.99 USD
Free Shipping on orders $49 and up

BMW Blue Auxiliary Coolant Reservoir Cap is the perfect upgrade for BMW owners looking to enhance both the aesthetics and functionality of their engine bay. Unlike generic aftermarket caps that overlook critical pressure regulation, this precision-engineered cap retains the OEM pressure release functionality, ensuring safe and reliable coolant system performance.

Crafted from high-quality billet aluminum, this reservoir cap offers superior durability and resistance to heat and fluids, preventing warping or degradation over time. Unlike adhesive-based cap covers that can loosen or fall off, this cap is a direct replacement for the factory component, providing a secure, high-performance solution.

  • OEM pressure release functionality – Maintains proper system regulation for optimal coolant performance
  • Premium billet aluminum construction – Offers enhanced durability and longevity
  • Direct replacement design – Secure fit without adhesives or modifications
  • Resistant to heat and fluids – Ensures long-lasting reliability in extreme conditions
  • Performance-inspired look – Adds a sleek, high-end appearance to your engine bay
  • Upgraded durability – Prevents cracking, leaks, and premature wear

Upgrade your BMW’s cooling system with the BMW Blue Auxiliary Coolant Reservoir Cap, blending performance, reliability, and premium styling.

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Bav Auto Temperature Sensor - BMW E39 E46 E9X E60 F01/02
10X Entries Into Our F80 M3 Sweepstakes
Bavarian Autosport - Corporate Logo
T#:639833
Part#: 13621433076
In Stock
Sale - Save 20% $ 14.99

This product was last offered at the strikethrough price on
05-03-2026

$ 11.99 USD
Free Shipping on orders $49 and up
Sale - Save 20%
$ 14.99

This product was last offered at the strikethrough price on
05-03-2026

$ 11.99 USD
Free Shipping on orders $49 and up
This is the coolant temperature sensor used in many BMW models from the late-1990s to the mid-2010s. The engine computer relies on the coolant temp to set the fuel mapping for the engine. As the car warms up the computer changes the fuel mixture. If your car is running a bit rich (too much fuel) it could be because this sensor is failing and not sending the correct info to the computer. This sensor is located in a variety of places depending on the engine. But it's one of those easy replacement items 'while you're in there' when doing a water pump or thermostat replacement. From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.
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